A photon-counting photodiode array detector for far ultraviolet (FUV) astronomy

A compact, stable, single-stage intensified photodiode array detector designed for photon-counting, far ultraviolet astronomy applications employs a saturable, 'C'-type MCP (Galileo S. MCP 25-25) to produce high gain pulses with a narrowly peaked pulse height distribution. The P-20 output phosphor exhibits a very short decay time, due to the high current density of the electron pulses. This intensifier is being coupled to a self-scanning linear photodiode array which has a fiber optic input window which allows direct, rigid mechanical coupling with minimal light loss. The array was scanned at a 250 KHz pixel rate. The detector exhibits more than adequate signal-to-noise ratio for pulse counting and event location

Characterizing upward lightning with and without a terrestrial gamma-ray flash

We compare two observations of gamma-rays before, during, and after lightning flashes initiated by upward leaders from a tower during low-altitude winter thunderstorms on the western coast of Honshu, Japan. While the two leaders appear similar, one produced a terrestrial gamma-ray flash (TGF) so bright that it paralyzed the gamma-ray detectors while it was occurring, and could be observed only via the weaker flux of neutrons created in its wake, while the other produced no detectable TGF gamma-rays at all. The ratio between the indirectly derived gamma-ray fluence for the TGF and the 95% confidence gamma-ray upper limit for the gamma-ray quiet flash is a factor of $1\times10^7$. With the only two observations of this type providing such dramatically different results -- a TGF probably as bright as those seen from space and a powerful upper limit -- we recognize that weak, sub-luminous TGFs in this situation are probably not common, and we quantify this conclusion. While the gamma-ray quiet flash appeared to have a faster leader and more powerful initial continuous current pulse than the flash that produced a TGF, the TGF-producing flash occurred during a weak gamma-ray "glow", while the gamma-ray quiet flash did not, implying a higher electric field aloft when the TGF was produced. We suggest that the field in the high-field region approached by a leader may be more important for whether a TGF is produced than the characteristics of the leader itself.Comment: 21 pages, 6 figures, accepted for publication by the Journal of Geophysical Research - Atmosphere

Considering the Use of Data by School Leaders for Decision Making: An Introduction

Our fifth book in the International Research on School Leadership series focuses on the use of data in schools and districts as useful information for leadership and decision making. Schools are awash in data and information, from test scores, to grades, to discipline reports, and attendance as just a short list of student information sources (Bernhardt, 2004), while additional streams of data feed into schools and districts from teachers and parents as well as local, regional and national policy levels (Henig, 2012; Honig & Venkateswaran, 2012; Piety, 2013). To deal with the data, schools have implemented a variety of data practices, from data rooms, to data days, data walks, and data protocols (Mandinach & Gummer, 2013; Marsh, 2012). However, despite the flood of data, successful school leaders are leveraging an analysis of their school’s data as a means to bring about continuous improvement in an effort to improve instruction for all students (Boudett & Steele, 2007). Nevertheless, some drown, some swim, while others find success. Our goal in this book volume was to bring together a set of chapters by authors who examine successful data use as it relates to leadership and school improvement. In particular, the chapters in this volume consider important issues in this domain, including: - How do educational leaders use data to inform their practice? - What types of data and data analysis are most useful to successful school leaders? - To what extent are data driven and data informed practices helping school leaders positively change instructional practice? - In what ways does good data collection and analysis feed into successful continuous improvement and holistic systems thinking? - How have school leadership practices changed as more data and data analysis techniques have become available? - What are the major obstacles facing school leaders when using data for decision making and how do they overcome them

The Multiple Futures of the Field of Educational Leadership Research and Practice – An Introduction

As the sixth volume in the International Research on School Leadership series, the contributing authors in this volume consider the history, challenges, and opportunities of the field of research and practice in educational leadership and administration in schools and districts. Ten years after the work of Firestone and Riehl (2005) and their contributing authors, our aim with the present volume was to summarize and update the work of the field, and provide a space to consider the multiple futures of educational leadership in schools and districts, as both challenges and opportunities. The first decade of the twenty-first century brought significant critiques, challenges, and competition to the research and practice of training leaders and administrators of schools and districts around the world. Congruently, the field experienced significant growth and change, as multiple new sub-domains flourished and were founded. Thus, in this volume we were delighted to included excellent chapters from multiple authors that considered the duality of the challenges and opportunities of: • The work of the field of educational leadership and administration research to date. • The opportunities and challenges of new visions of leadership in traditional and non-traditional schools. • The evolving state of research evidence in educational leadership and the increasing sophistication of multiple methodologies, including qualitative research, quantitative modeling, the ability to test theory, and the increasing opportunities brought on by the intersection of data, research, and practice. • The preparation of educational leaders. • And the emerging trends in the professional development of school leaders. The authors of the nine chapters in the present book volume took on this challenge of confronting the duality of not only including the past as we look to the future, but also the duality of the critique of the field in the midst of exciting and significant progress in our knowledge and understanding of leadership in schools. In the first section of the book (Chapters 2, 3 and 4), the authors examine the interplay of educational leadership research and theory as it relates to reform in schools, especially as it relates to serving historically underserved populations globally. In section 2 (Chapters 5 and 6), the authors highlight the importance of methodological considerations in school leadership research as a means to understand theory and practice as well as providing interesting avenues that point to multiple exciting future possibilities through relying on current innovations noted within the chapters. Section 3, (Chapters 7 and 8) examine the research and practice of school leadership preparation, especially as it relates to university-district partnerships and non-traditional school settings. And in the final chapter, (Chapter 9), our capstone contributor provides a means to link the present volume with the past writings on these topics, while also providing a lens to view the exciting possibilities and promises of the multiple futures of the field of educational leadership research and practice

The Multiple Futures of the Field of Educational Leadership Research and Practice – An Introduction

As the sixth volume in the International Research on School Leadership series, the contributing authors in this volume consider the history, challenges, and opportunities of the field of research and practice in educational leadership and administration in schools and districts. Ten years after the work of Firestone and Riehl (2005) and their contributing authors, our aim with the present volume was to summarize and update the work of the field, and provide a space to consider the multiple futures of educational leadership in schools and districts, as both challenges and opportunities. The first decade of the twenty-first century brought significant critiques, challenges, and competition to the research and practice of training leaders and administrators of schools and districts around the world. Congruently, the field experienced significant growth and change, as multiple new sub-domains flourished and were founded. Thus, in this volume we were delighted to included excellent chapters from multiple authors that considered the duality of the challenges and opportunities of: • The work of the field of educational leadership and administration research to date. • The opportunities and challenges of new visions of leadership in traditional and non-traditional schools. • The evolving state of research evidence in educational leadership and the increasing sophistication of multiple methodologies, including qualitative research, quantitative modeling, the ability to test theory, and the increasing opportunities brought on by the intersection of data, research, and practice. • The preparation of educational leaders. • And the emerging trends in the professional development of school leaders. The authors of the nine chapters in the present book volume took on this challenge of confronting the duality of not only including the past as we look to the future, but also the duality of the critique of the field in the midst of exciting and significant progress in our knowledge and understanding of leadership in schools. In the first section of the book (Chapters 2, 3 and 4), the authors examine the interplay of educational leadership research and theory as it relates to reform in schools, especially as it relates to serving historically underserved populations globally. In section 2 (Chapters 5 and 6), the authors highlight the importance of methodological considerations in school leadership research as a means to understand theory and practice as well as providing interesting avenues that point to multiple exciting future possibilities through relying on current innovations noted within the chapters. Section 3, (Chapters 7 and 8) examine the research and practice of school leadership preparation, especially as it relates to university-district partnerships and non-traditional school settings. And in the final chapter, (Chapter 9), our capstone contributor provides a means to link the present volume with the past writings on these topics, while also providing a lens to view the exciting possibilities and promises of the multiple futures of the field of educational leadership research and practice

Satisfaction of Mortgage

Satisfaction of Mortgage between J. J. Freeze to G. M. D. Bowers and B. R. Colson. The document is dated 11 April 1914

1 May 1913 property agreement

Agreement between G. M. D. Bowers, W. W. Colson, and B. R. Colson to hold Dixieland Park land for Theophilus Brown Larimore. The one-page typewritten document is dated 1 May 1913

[Unsigned agreement to hold land unchanged for Larimore]

Unsigned agreement on Our Florida Friend letterhead where G. M. D. Bowers, W. W. Colson, and B. R. Colson agree to hold land for Theophilus Brown Larimore unchanged. The agreement is one-page typewritten and dated 1 May 1913

The Lemaitre-Schwarzschild Problem Revisited

The Lemaitre and Schwarzschild analytical solutions for a relativistic spherical body of constant density are linked together through the use of the Weyl quadratic invariant. The critical radius for gravitational collapse of an incompressible fluid is shown to vary continuously from 9/8 of the Schwarzschild radius to the Schwarzschild radius itself while the internal pressures become locally anisotropic.Comment: Final version as accepted by GR&G (to appear in vol. 34, september 2002

Vertical migration maintains phytoplankton position in a tidal channel with residual flow

A tidal channel can retain phytoplankton, despite a residual flow, if the phytoplankton migrate vertically with a daily rhythm. Tidal currents are slowed down by bed friction and so plankton experience faster flow when higher in the water column. The lateral movement of the plankton depends on the nature of the vertical migration, particularly the time spent near the surface and the phase of the tide. A model of this process accorded with observations of chlorophyll derived from in situ fluorescence at a mooring in a tidal channel. Peaks in chlorophyll at the end of the flood tide indicated the presence of a phytoplankton bloom downstream of the mooring. Peaks in chlorophyll at the ends of the morning flood tides were 3 to 4 times larger than at the ends of the evening floods, over several days. In contrast, well-mixed particulates were removed from the channel by the residual flow in just 2 d. Both the day-night asymmetry and the sustained presence of chlorophyll were explained by allowing for vertical migration of the phytoplankton and constraining the period during which they were near the surface. Tidal channels retaining phytoplankton that migrate vertically can be ecologically more diverse and yield higher commercial output of farmed bivalves. The natural timings of some phytoplankton blooms in tidal channels are controlled by the nature of the migration. Although a by-product of vertical migration, longer residence in the tidal channel affords the phytoplankton more nutrients than phytoplankton that advect offshore